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A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 Khai11 2130
#2 HeilEuler 1995
#3 ckha 1843
#4 miscitaofvh 1830
#5 NoSpaceAvailable 1760
Recent Solves
Jack's Birthday Confusion leireretana
Diffie-Hellman Starter 4 tommyknocker
Point Addition shanesully
Everything is Big bien
Lazy CBC Kohlrabi
Recent Solutions
Twin Keys offPath 0
PriMeD5 offPath 0
RSA Starter 3 tommyknocker 0
Greatest Common Divisor DRAL3N 0
Structure of AES TopAce 0

Level Up

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